Once the knowledge is created, transferred and retained, individuals apply the knowledge when interacting with the ES. Markus (2001) suggests that the source of competitive advantage resides not in knowledge itself, but in the application of the knowledge. Effective ‘‘knowledge application” is important in every phase of the ES lifecycle, particularly in maintenance and upgrades (Markus et al., 2003), and is a frequent organizational concern that appears to be closely related to ES-success (Ross et al., 2003; Sumner, 2003).